I guess the question is what is spacetime made of, which is the big problem in physics right now. Whether it's loop quantum gravity, string theory, or one of th

I guess the question is what is spacetime made of, which is the big problem in physics right now. Whether it's loop quantum gravity, string theory, or one of the many other theories that exist, the question of what is spacetime is what people are trying to solve to figure out quantum gravity. What is spacetime made of? Nobody knows yet.